I have just installed my HID kit with A6 projectors and I noticed that one of my bulbs have a slightly different tint than the other.

One is a Philips and the other is an Osram. The Osram seems yellowish while the philips seems bluer and sharper.

What could cause the color difference? It's pretty noticable and people have told me the (Osram) bulb seems dimmer.

Different brand of bulbs does have different colours. Even bulbs of the same brand could have varying colour due to hour of use.

Read the FAQ page as there is more detail.

Why are you using 2 different mfg. bulbs? Availability? Short term I hope....

When I bought the HID kit it came with 2 Philips bulbs but for some reason one of them didn't work so I bought one on Ebay for $35 and I had no idea it was going to be an Osram.

Any problems with using two different bulbs?

-Ryan

Osrams are high quality as well, so you are not risking anything. It can get risky to put in non OEM bulbs.

Maybe you should get another Osram bulb from the same source to match and keep the Philips as a spare.